Portable hand tools are in common use. These tools are relatively inexpensive to purchase and convenient to use. The two major problems encountered are the safety of the worker and accuracy of the work performed. To overcome these problems many solutions have been proposed. One of the most common proposals is attachments such as guides and supports for use with the tools. Most of these devices require that one or both hands be on the tool with no separate provision made for stabilization of the attachment. When a separate provision is made, it is usually necessary to balance the force applied to the tool.
It is common to have the line of force that is applied to the tool, and/or guide, project outside and beyond the guide base. This creates a clumsy hold and a torque that tends to move the guide and prevent an accurate location and maintenance of the guide on the work, and tends to preclude an accurate and constant angle for tool advancement. Examples are the patents to A. J. Daniels, U.S. Pat. No. 2,831,376 issued Apr. 22, 1958 and E. W. Purkey, U.S. Pat. No. 3,250,153 issued May 10, 1966. To balance this force or torque, handles have been added; A. C. Carles, U.S. Pat. No. 2,953,045, issued Sept. 20, 1960 and R. O. Hudson, U.S. Pat. No. 4,080,092, issued Mar. 21, 1978. Even when one of the forces on the tool or a handle is in line with the area encompassed by the base, the other is placed in opposition to that force or creates a torque with respect to it; J. P. Pufahl, U.S. Pat. No. 3,100,408, issued Aug. 13, 1963 and L. E. Pugsley, U.S. Pat. No. 3,107,556, issued Oct. 22, 1963.
When guideways are associated with tools they are often circular and either permit rotation of the tool about the guide or require two posts; L. J. Leitner et al, U.S. Pat. No. 2,837,939, issued Jun. 10, 1958 and I. J. Epstein, U.S. Pat. No. 4,279,552, issued July 21, 1981. Those that are not circular are placed on the side of the tool or opposite the tool grip, reducing visibility and the ability of the tool to access areas such as corners; M. Van Praag, U.S. Pat. No. 3,242,773, issued Mar. 29, 1966 and G. C. Lipe, U.S. Pat. No. 3,746,460, issued Jul. 17, 1973. Non-circular posts, adjustable stops on posts, and graduations on posts, per se, are old in the art; A. T. Abell, U.S. Pat. No. 3,853,420, issued Dec. 10, 1974, N. A. Lopez, U.S. Pat. No. 2,050,709, issued Aug. 11, 1936, and A. Boyajian, U.S. Pat. No. 3,838,935, issued Oct. 1, 1974.